No one would write a law with such language in the United States so if you have a Tennessee appellate case you'll have to share. I doubt this "rule" exists, for example 150 lb man hits 300 lb bouncer with two solid blows which do no harm, does bouncer have the right to use potentially deadly force on the guy? No.

I will admit I am passing on heresay, I was talking to a bail chaser, asking him questions about the legality of being a bail chaser. Or for those who prefer the term "Bounty Hunter."

And that's the answer he gave me, and I'm not pretending that is the actual wording of the law. He said that the strikes, blows, are relative to the situation, but were talking if two people are equally matched, and one is assaulting the other, not the two are about to engage in a mutual exchange of fisticuffs.

I'm am probably entirely full of **** though, so I will see if I can't track down the actual legislature on what consitutes self defense when deadly force is involved.

It doesn't matter how "scary" your knife or gun looks. Unless it has features which are specifically prohibited, it is legal. There is usually no law against carrying a full blown race gun for protection. Can carrying the gun be used against you in court? Of course as they can say that a gun with a light aftermarket trigger trigger is dangerous since the chances of accidental discharges (AD) are higher. However, if you did carry a bling bling piece like that chances are you would've had extensive training and competition which you can use to defend yourself by proving that you have the knowledge and competence to carry such a gun. And even if you didn't, it's still not against the law. A cop may pull you over for having a huge spoiler on your car. Is having one illegal? Hell no.

It all goes to intent though. If you are attacked and desperately stab someone with your swiss army knife to save your life, you're unlikely to have been looking for trouble. If you stab someone with your "Assassin" brand spring-loaded butterfly knife with patented "Kill-o-matic" action, the police and prosecutors may wonder exactly why you went out of your way to have such a deadly weapon. perhaps you were looking for an excuse to use it because you're an RBSD gun bunny. Intent is everything.